Title : Supplementation of corn-soy based diets with phytase: Effects on digestibility of amino acids in male broiler chicks ( Supplementation of corn-wheat-soy-based diets with phytase: Effects on digestibility of amino acids in broiler chicks )

An experiment was conducted to evaluate the effects of microbial phytase on productive traits and apparent digestibility of Amino Acids (AA) in male broiler chickens. The experiment was a completely randomized design. Each treatment consisted of 5 replicates of 12 male broilers, for a total of 300 Ross broiler chicks. Broiler chickens were fed similar diets containing 5 levels of phytase (0, 250, 500, 750 and 1,000 FTU/kg of diet) from 1-28 days of age. Excreta were quantitatively collected from 21-24 days of the experiment. The excreta stored at -20°C, freeze-dried and analyzed for amino acids. During the experiment, Body Weight (BW), Average Daily Gain (ADG), Average Daily Feed Intake (ADFI) and Feed Conversion Ratio (FCR) were measured weekly. Total 250 and 500 FTU phytase supplementation significantly increased (p<0.05) apparent AA digestibility. Higher levels of phytase decreased AA digestibility in compare to 250 and 500 FTU. Phytase had no significant effect (p>0.05) on body weight, feed intake and feed efficiency up to 28 days of age.